21100461 has 8 divisors (see below), whose sum is σ = 28196064. Its totient is φ = 14035920.

The previous prime is 21100447. The next prime is 21100463. The reversal of 21100461 is 16400112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21100461 - 2¹⁸ = 20838317 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21100461.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100463) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6130 + ... + 8931.

It is an arithmetic number, because the mean of its divisors is an integer number (3524508).

Almost surely, 2^21100461 is an apocalyptic number.

It is an amenable number.

21100461 is a deficient number, since it is larger than the sum of its proper divisors (7095603).

21100461 is a wasteful number, since it uses less digits than its factorization.

21100461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15531.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 21100461 is about 4593.5238107579. The cubic root of 21100461 is about 276.3316612590.

Adding to 21100461 its reverse (16400112), we get a palindrome (37500573).

The spelling of 21100461 in words is "twenty-one million, one hundred thousand, four hundred sixty-one".